The present embodiments relate to a method for determining a unique spatial relation of a medical device to an object. The medical device includes a registration mechanism. The embodiments also relate to a medical device with a registration mechanism by which a spatial relation of the medical device to an object may be determined by a first method for determining a relation of this kind.
In medical scenarios, there may be interaction between at least one medical device and an object (e.g., a patient or another medical device). At the same time, in many cases, it is decisive that a medical device has a prespecified unique spatial relation to the object so that movements of the medical device or a movable component of the medical device take place in a precise relative position (e.g., a unique spatial relation to the object). The determination of the spatial relation of the medical device to the object is also referred to as registration. In many scenarios, this registration is relevant for the safety of patients and staff (e.g., to avoid collisions between medical devices or medical devices and patients).
For example, a registration that takes place using a contact-free method in an image-based manner (e.g., with the “Mako” robot using fluorescence-based markers) may be afflicted with errors. An error of this kind is particularly critical if the error may have a fatal outcome. For example, errors may occur in a robotic minimally invasive surgical intervention by a medical device in which a medical robotic device performs autonomous movements in the patient or in the vicinity of the patient and these movements are controlled by image data to which the medical device was possibly incorrectly registered (e.g., incorrectly placed in a unique spatial relationship).
If fatal events of this kind are at all feasible, it must not be possible for one single error to be sufficient to allow a fatal event of this kind actually to take place. Preventing all critical errors from occurring is known as the so-called first-fault safety. One possibility of achieving this first-fault safety is to anchor the medical device to a firmly defined position relative to the object. For example, anchoring the medical device is achieved by the “Perfint” system where the medical device is firmly anchored in the ground. However, anchoring the medical device restricts the flexibility of the positioning of the medical devices to an extreme degree.